Extra-radioactive clock.
This clock has an unusually large amount of radium paint on its numerals and hands, making it more radioactive than the average antique luminous hand clock. Although I have not tried this, the seller claims that if you look at the hands with a magnifying glass in a dark room you can see individual flashes of light, which says more about how decayed the phosphors are than about the amount of radioactivity. (When new the hands would have glowed too brightly to see individual flashes, but over time the phosphors in these clocks degrades. The radioactivity will stay for thousands of years.)Source:eBay seller vonhohoContributor:Theodore GrayAcquired:8 February, 2009Text Updated:8 February, 2009Price: $159Size: 4"Purity: <0.1%